Penetration and Displacement Behavior of N2 in Porous Interlayer Structures Containing Water/Salt Component by Molecular Dynamics Simulation

The penetration and displacement behavior of N2 molecules in porous interlayer structures containing a water/salt component with porosities of 4.29%, 4.73%, 5.17%, 7.22%, and 11.38% were explored using molecular dynamics simulations. The results demonstrated that the large porosity of the interlayer structures effectively enhanced the permeation and diffusion characteristics of N2. The water and salt in the interlayer structures were displaced during the injection of N2 in the porosity sequence of 4.29% < 4.73% < 5.17% < 7.22% < 11.38%. The high permeance of 7.12 × 10−6 indicated that the interlayer structures with a porosity of 11.38% have better movability. The strong interaction of approximately 15 kcal/mol between N2 and H2O had a positive effect on the diffusion of N2 and the displacement of H2O before it reached a stable equilibrium state. The distribution of N2 in porous interlayer structures and the relationship between the logarithm of permeability and breakthrough pressure were presented. This work highlighted the effects of porosity on the permeability and diffusion of N2/H2O in the interlayer, thus providing theoretical guidance for the development of petroleum resources.

Proactive design and technological developments to solve the problems of costly construction on saline soils

Modern development territories composed of saline silty-clayey soils is not provided with the proper quality, and therefore requires deep scientific studies, which must be continued in the process of research, design, construction and operation of projected facilities with constant adaptation of the proposed proactive structural and technological developments to changing conditions flowing in these soils under anthropogenic impact on the salt component of the soil.

Salts in the base soils as a factor forming their corrosion activity, subsidence and compressibility

Saline silty clay soil (SSCS) is the stochastic spatio-temporal separation of a common territory, which changes under conditions of natural and man-made impact on the salt component of soil. The research methodology of SSCS is proposed here. The design parameters determined by the proposed methodology allow to take into account the entire spectrum of changes in the properties of the SSCS in the base for the standard service life of the designed facility at the design stage, and, therefore, to select reliable geotechnology for construction of the designed facility, thereby ensuring its reliable operation.

FEATURES OF BEHAVIOR OF ORGANIC AMMONIUM SALTS WHEN ISOLATING RUBBER FROM LATEX

The influence of low-and high-molecular substances on the stability of various lyophobic colloidal systems is among the earliest empirical and intuitively used phenomena. The water-soluble organic salts are applied in different industries including latex technology. This is related to a complex of various colloid-chemical phenomena and their interaction with latex dispersed phase and its components. Nowadays some high-molecular and low-molecular organic reagents are used to reduce the aggregate stability of latex system on an industrial scale. In the article, the coagulating ability of ammonium acetate, ammonium oxalate and ammonium citrate were estimated for the latex coagulation in the comparison with an inorganic ammonium salt and sodium chloride. The influence of the nature of salt component, as well as its consumption, on the technological features of the coagulation process in the emulsion latex was established. The relationship between the consumption of organic ammonium salt and acidifying component on the complete coagulation was shown. It’s worth noting that the strength of the acid, which forms the ammonium salt, has an effect on the technological extraction process of rubber from latex. The stronger the organic acid, the lower the consumption of the acidifying agent, and complete coagulation is achieved at lower consumption of coagulants. Peculiar behavior of ammonium citrate has been noted: complete coagulation wasn’t achieved with the consumption of this salt over 200 kg/t of rubber and increased consumption of the acidifying agent. It can be due to the fact that citric acid is an oxyacid and shows properties characteristic for surfactants and increases the aggregate stability of the system. These rubbers, rubber compounds and vulcanizates obtained correspond to standard parameters.

Evidence for brown carbon absorption over the Bay of Bengal during the southwest monsoon season: a possible oceanic source

Light-absorbing brown carbon aerosols can have a marine origin over the coastal oceans and are likely associated with the sea salt component emitted from the ocean surface – significantly contributes to aerosol radiative forcing.

A New Route for Direct Electroless Ni-P Plating on Magnesium Alloys

This report describes a new route for direct electroless Ni-P plating on magnesium alloys using nickel sulfate as the main salt component. The surface morphology, chemical composition and corrosion resistance of coatings were determined using SEM, EDX and electrochemical polarization techniques. Ni-P coatings with good corrosion resistance and high adhesion were obtained using this route and improved pretreatments. A mixture of H3PO4 and HNO3 was used as a pickling solution for Mg substrate pretreatment. A coarse surface was produced via the developed pickling procedure. A mechanical occlusive force is believed to exist between the coatings and the substrates. Twice activations, K4P2O7 and NH4HF2 as activation components, respectively, were applied for the pretreatment of magnesium alloy plating. An optimal F/O ratio on the Mg substrate surface was obtained by this pretreatment method. The activation film has insoluble partial fluorides which can depress the active points on substrate surface against the reaction of Mg with Ni2+ and H+ in the plating bath. A highly stable bath with pH 5 buffer was identified. The advantages of the developed process include chromium-free, low fluoride, and high bath stability. It is applicable for the production of motorcycle part plating.

Composition of 15–80 nm particles in marine air

The chemical composition of 15–80 nm diameter particles was measured at Mace Head, Ireland, during May 2011 using the TDCIMS (Thermal Desorption Chemical Ionization Mass Spectrometer). Measurable levels of chloride, sodium, and sulfate were present in essentially all collected samples of these particles at this coastal Atlantic site. Organic compounds were rarely detectable, but this was likely an instrumental limitation. Concomitant particle hygroscopicity observations usually showed two main modes, one which contained a large sea salt component and another which was likely dominated by sulfate. There were several occasions lasting from hours to about two days during which 10–60 nm particle number increased dramatically in polar oceanic air. During these events, the sulfate mode increased substantially in number. This observation, along with the presence of very small (<10 nm) particles during the events, suggests that the particles were formed by homogeneous nucleation, followed by subsequent growth by sulfuric acid and potentially other vapors. The frequency of the events and similarity of event particles to background particles suggest that these events are important contributors of nanoparticles in this environment.